How do you solve #7/9=b/(b-10)#?

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Answer 1 · 2016-07-10T03:05:25

#7/9 = (b)/(b-10)#

By cross-multiplying, namely

#7*(b-10)# and #9*(b)#, we get

#7b-70=9b#

Subtracting #7b# from both sides yields

#-70 = 2b#, and dividing both sides by #2# yields

#b = -35#